1,3 Propanediol

3 propanediol (PDO) is an important precursor for plastic manufacturing as well as an effective solvent Although PDO has been known as a product of glycerol fermentation for many years (Freund, 1881), its commercial relevance has increased since Dupont began 

3- Propanediol (1,3PD) is also undergoing a transition from a small-volume specialty chemical into a commodity. The driving force is its application in poly (trimethylene terephthalate) (PTT), which is expected to partially replace polyethylene terephthalate) and polyamide because of its better performance, such as stretch recovery. The projected market volume of PTT under the trade-names CORTERRA (Shell) and Sorona 3GT (Dupont) is 1 Mt a-1 within a few years. In consequence, the production volume of 1,3PD is expected to expand from 55kta-1 in 1999 to 360 kt a-1 in the near future. 1,3PD used to be synthesized from acrolein by Degussa and from ethylene oxide by Shell (see Fig. 8.8) but a fermentative process is now joining the competition. 

The Degussa process (now owned by Dupont) starts from acrolein, which is hydrated in the presence of an acidic ion exchanger into 3-hydroxypropanal (3HP, Fig. 8.8 a). The latter is subsequently extracted into isobutyl alcohol and hydrogenated over a Ni catalyst [53]. The overall yield does not exceed 85%, due to competing water addition at the 2-position and ether formation in the initial step. It has been announced that Degussa will supply up 10 kt a-1 to Dupont until the fermentative process of the latter company (see below) comes on stream [54]. 

Shell produces 1,3 PD from ethylene oxide via hydroformylation with synthesis gas (Fig. 8.8 b). The transformation required two separate steps in the past [55], but has been improved [56], which made the large-volume use of 1,3PD in poly(trimethylene terephthalate) economically viable, and the two steps have been telescoped into one [57, 58]. Shell has a capacity to 70 kt a-1 [59]. 

The fermentation of 1,3PD from glycerol (see Fig. 8.8c) was discovered in the late 19th century [60]. It has since been found that a considerable number of bacteria can use glycerol as a source of carbon and energy under anaerobic conditions and the reaction pathways have been elucidated [61]. Out of every three molecules of glycerol, one is oxidized, phosphorylated into DHAP and subsequently metabolized via the glycolysis pathway and the TCA cycle the other two are converted into 1,3PD, to maintain redox balance (see Fig. 8.9), via dehydration and NADH-driven reduction. 

There has been a long-standing interest in the possible microbial production of 1,3PD from glycerol in Citrobacter, Klebsiella and Clostridia species [61-63], to 

According to the following data 1,2-propanediol is mostly regarded as non-toxic. LD50 oral subcutaneous LD50 intravenous LD50 dermal (exposure 24 h) 

Rabbit skin (exposure 4 h) no skin irritation, but slight eye irritation. 

Ecotoxicity Similar to 1,2-ethanediol (1.13.). Relatively non-persistant and of low aquatic toxicity (Kent et ak, 1999). 

YAQIN SUN, CHENGWEI MA, HONGXIN FU, YING MU, and ZHILONG XIU School of Life Science and Biotechnology, Dalian University of Technology, Dalian, PR China 

Biopwcessing of Renewable Resources to Commodity Bioproducts, First Edition. Edited by Virendra S. Bisaria and Akihiko Kondo. 

3- propanediol from biotechnology is discussed for its industrial production. 

Previously, PTT was produced based on 1,3-PD by chemical synthesis. The traditional chemical routes of commercial synthesis for 1,3-PD production are from acrolein by DuPont and from ethylene oxide by Shell. The route of DuPont is that acrolein is converted to 3-hydroxypropionaldehyde (3-HPA) by hydration, followed to produce 1,3-PD by hydrogenation (Lawrence and Sullivan, 1972). Shell followed the method of hydroformylation of ethylene oxide to 3-hydroxypropanal. This is subsequently extracted and hydrogenated for the production of 1,3-PD (Sullivan, 1993). 

The overall 1,3-PD yield from glucose in the two-stage process with E. coli and K. pneumoniae reached only 0.17 g/g. 

Alternate Name 4-(chloromethyl)pyridine hydrochloride. Physical Data mp 160-163 °C. 

Form Supplied in white or off-white crystaUine solid available from several commercial sources. 

Handling, Storage, and Precautions the free base is reported to be unstable, and should be generated shortly before use. 

Protection Reagent Alcohols (eq 1) - (including hydroxy-containing amino acid derivatives), phenols, carboxylic acids (eq 2), and thiols (eq 3) have all been alkylated by this reagent (1). Esters (2) are also available from the respective acids by 1,3-Dicyclohexylcarbodiimide coupling with 4-pyridylmethanol in CH2CI2 in comparable yield. 

Albericio, F. Romero, G. Garcia-Echeverria, C. Claret, J. Muller, C. Giralt, E. Pedroso, E. JOC1988,53,5386. 

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The main intermediates in the pentaerythritol production reaction have been identified and synthesized (50,51) and the intermediate reaction mechanisms deduced. Without adequate reaction control, by-product formation can easily occur (52,53). Generally mild reaction conditions are favored for optimum results (1,54). However, formation of by-products caimot be entirely eliminated, particularly dipentaerytbritol and the linear formal of pentaerythritol, 2,2 -[meth5lenebis(oxymethylene)]bis(2-hydroxymethyl-1,3-propanediol) [6228-26-8] ... 

Temperature, °C Glycerol trinitrate Ethylene glycol dinitrate Diethjlene glycol dinitrate 1,2-Propylene glycol dinitrate 1,3-Propanediol dinitrate... 

In acetic acid solvent, ethylene gives 1,3-propanediol acetates (46) and propylene gives 1,3-butanediol acetates (47). A similar reaction readily occurs with olefinic alcohols and ethers, diolefins, and mercaptans (48). 

Propylene glycol, dipropylene glycol, and tripropylene glycol all have several isomeric forms. Propylene glycol has one asymmetric carbon and thus there are two enantiomers (R)-I,2-propanediol and (3)-1,2-propanediol. 1,3-Propanediol is a stmctural isomer. Dipropylene glycol exists in three stmctural forms and since each stmctural isomer has two asymmetric carbons there are four possible stereochemical isomers per stmcture or a total of twelve isomers. These twelve consist of four enantiomer pairs and two meso- compounds. Tripropylene glycol has four stmctural isomers and each stmctural isomer has... 

Neopentyl glycol, or 2,2-dimethyl-1,3-propanediol [126-30-7] (1) is a white crystalline soHd at room temperature, soluble ia water, alcohols, ethers, ketones, and toluene but relatively iasoluble ia alkanes (1). Two primary hydroxyl groups are provided by the 1,3-diol stmcture, making this glycol highly reactive as a chemical intermediate. The gem-A methy configuration is responsible for the exceptional hydrolytic, thermal, and uv stabiUty of neopentyl glycol derivatives. 

Preparation. The industrial production of malonic acid is much less important than that of the malonates. Malonic acid is usually produced by acid saponification of malonates (9). Further methods which have been recendy investigated are the ozonolysis of cyclopentadiene [542-92-7] (10), the air oxidation of 1,3-propanediol [504-63-2] (11), or the use of microorganisms for converting nitriles into acids (12). 

The nitro alcohols in Table 1 are manufactured in commercial quantities however, three of the five of them are used only for the production of the corresponding amino alcohols. 2-Methyl-2-nitro-l-propanol (NMP) is available as the crystalline soHd or as a mixture with siHcon dioxide. 2-Hydroxymethyl-2-nitro-1,3-propanediol is available as the soHd ( 9.15/kg), a 50% solution in water ( 2.33/kg), a 25% solution in water ( 1.41/kg), or as... 

Glycol Titanates. Primary diols (HOGOH), such as ethylene glycol and 1,3-propanediol, react by alkoxide interchange at both ends, yielding insoluble, white soflds that are polymeric in nature (18,61—63) ... 

Reaction of TYZOR DC and 1,3-propanediol gives titanium 1,3-propylenedioxide bis(ethyl acetoacetate) [36497-11-7J, which can be used as a noncorrosive curing catalyst for room-temperature-vulcanizing siUcone mbber compositions (99). Similar stmctures could be made, starting with titanium bis-acetylacetonates, such as that shown in stmcture (9). 

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